Academic literature on the topic 'Alfa relaxace'

This master‘s thesis presents the problems of EEG bio-feedback and its application for relaxing a person. It deals with the requirements of the sensing electrode and the biological signal amplifiers. The main substance of my thesis is the proposal of Alpha monitor, a device that uses the electrical activity of alpha brain waves for the realization of biological EEG feedback. The device concept takes into consideration the requirements of users’ security and also characteristics of alpha activity, which define the requirements for signal processing circuits and for propositions of the aural transducer. This master‘s thesis analyses given submission, proposes particular circuits, presents the overall electrical diagram and the list of components. The overall electrical diagram and single circuits are drawn within the EAGLE 5.7.0.

The master´s thesis presents the problems of EEG biofeedback and its application to relax people. The first part discusses the properties of EEG signal , the requirements of the standard EEG and also distribusion signal into different frequency bands. The main essence of the work is the design and realization of Alfa Monitor – a device for relaxation , that for implamanting EEG biofeedback uses acoustic form and sensing of electrical activity of brain in the region of alpha waves. The second half of the work is t focused on circuit design, using integrated circuits with component values of relevant calculations . Further, it analyzes the practical implementation of alfa monitor. The last chapter is devoted to the testing the functionality of this device.

This work deals with problems of EEG biofeedback and possibilities of its use in therapy. The method of EEG biofeedback helps patients to achieve the state of relaxation. It is a noninvasive treatment modality. The paper also discussed the requirements for each component unit. The main point of a design and construction of Alpha activity monitor, a device implementing EEG biofeedback focused on sensing electrical activity of the brain, specifically alpha waves. Alpha activity is specific and their parameters are taken into account when selecting components and construction equipment. Custom feedback is then for the appearance of alpha activity mediated by the headphones in acoustic form. The work also includes design of electrical circuits and electrical diagram of the overall apparatus including a list of used parts. Electrical diagrams are formed in the EAGLE 6.1.0.

The aim of this work is to study the effect of thermal history to structure and properties not only of oriented polypropylene monofilaments with different orientation but of course of isotropic non-oriented polypropylene. Term thermal history includes thermal regimes from alpha relaxation temperature (T?) to melting temperature (Tm). This work consists of three parts. The changes of dynamic mechanical properties, strength, deformation and tensile modulus of polypropylene samples according to annealing temperature (Ta) are described in the first part of this work. In the second part, the changes of crystal phase are observed. Preferentially, calorimetric behaviour (DSC), changes of crystal dimensions and orientation function of crystal phase (X-ray) are observed. Measured values from the first and the second part of this work were used for calculation of total orientation function of PP samples. Rheological measurements are shown in the third part of this thesis. Rheological measurements consist of short isothermal creep, shrinkage of free tapes and static deformation at higher temperatures. Measured rheological values were performed using rheological models. Using these models characteristics of entropic spring, instantaneous elasticity and viscosity and tendency to get to state of ease were calculated.

The diploma thesis is based on the study of hydrophobic interactions of the native hyaluronan with selected solutes. On the basis of a literature search were chosen fluorescent probes and fluorescing biologically active substances, which are useful for investigation of colloids as 6-(p-toluidino)-2-naphthalenesulfonic acid (polarity probe), lipophilic vitamin (±)-alpha-tocopherol, pyrene (polarity probe) and finally hydrophilic vitamin riboflavin. In the experimental part of this thesis was studied the influence of solvents with different polarities, or more precisely dielectric constant, on the emission spectra, as well. There were investigated interactions of native hyaluronan with TNS and then interactions, which were influenced by the ionic strength. Such influenced interactions were not observed, that was probably due to the strong solvation´s wrapping of the hyaluronan. Interactions were observed after the process of lyophilisation followed-up by the rehydratation of the samples. For the next study of interactions the riboflavin was chosen and was investigated the REES effect in the native hyaluronan in different concentrations of its different molecular weights. In this case were not observed any shifts in the emission maximum with the excitation wavelenght shift and that is why the interactions of hyaluronan with riboflavin were not demonstrated in the field of chosen concentrations. By using another probe alpha-tocopherol was investigated the associative behaviour of hyaluronan and moreover was observed anisotropy of alpha-tocopherol in different concentrations of different molecular weights of native hyaluronan. The anisotropy reached high values in contrast to the reference solute that was the mixture of glycerol and ethanol. The anisotropy depended more on the molecular weight than on the concentration of hyaluronan. Interactions of hyaluronan were also studied by using the polarity probe pyrene in different concentrations of different molecular weights of the hyaluronan. The pyrene 1:3 ratio did not show the concentration dependence within the chosen concentrations except for the molecular weight 253.9 kg mol–1. Both probes alpha-tocopherol and pyrene were performed by the process of lyophilisation followed-up by the rehydratation, which improved interactions of these probes with hyaluronan.